RNA splicing and transcription are two points at which gene expression can be regulated. A lack of control at these key points can lead to cellular misfunction that includes cancer or human genetic disease. Both processes occur in close proximity to each other in the cell's nucleus, and it appears that splicing and transcription occur coincidently. It has previously been shown that a Drosophila SR protein, B52, is an essential splicing factor in vitro. Interestingly, B52 has characteristics that suggest it is more than an RNA-binding, splicing factor. B52 associates with decondensed regions in chromatin structure around transcription loci in vivo, a distribution different from other splicing factors. The aim of this work is two-fold. (1) To investigate the possible functional role of B52 in pre-mRNA splicing in vivo using reverse genetics in Drosophila melanogaster. (2) To analyze how B52 obtains its distinct distribution at active transcription loci by searching for proteins with which it interacts using the yeast two-hybrid system as an open ended screen. By identifying proteins that interact with B52 it is possible that a link between its function as a splicing factor and a chromosomal protein will be illuminated.